Restore Apple Firmware - Screen Black

Restore Mac firmware

Does your Mac turn on, but the screen stays black? After a failed macOS update, does only an exclamation mark appear, or does the Mac no longer start properly at all? In rare cases, damaged or incomplete firmware can be the cause.

On a Mac with an Apple chip or an Intel Mac with the Apple T2 Security Chip, you can revive or completely restore the firmware using a second Mac.

In this updated guide, we show you step by step how to revive or restore Mac firmware in DFU mode and explain the important difference between reviving without data loss and a complete restoration.

When might firmware reviving be necessary?

Apple lists several situations where a Mac's firmware needs to be revived or restored.

Typical symptoms include:

• The Mac starts, but the screen stays permanently black on the second Mac.
• An exclamation mark in a circle appears at startup.
• A macOS update or installation was interrupted.
• The Mac displays the status indicator pattern for firmware recovery mode.
• macOS can no longer be installed even through Recovery.
• The Mac no longer responds as expected after a failed update.

One possible cause is a power interruption during installation. In such cases, the firmware or Recovery system may have been written incompletely.

Which Macs can be revived this way?

The DFU procedure described here works on:

• Macs with Apple chips – for example M1, M2, M3, M4 and newer generations
• Intel Macs with the Apple T2 Security Chip

These include many models from the following product lines:

• MacBook Air
• MacBook Pro
• Mac mini
• Mac Studio
• iMac
• iMac Pro with a T2 chip
• Mac Pro with a T2 chip or Apple chip

What do you need to revive the firmware?

You need:

• the affected Mac with an Apple chip or T2 Security Chip,
• a second working Mac, known as the host Mac,
• on the host Mac, macOS 14 Sonoma or later,
• a working internet connection,
• enough free storage on the host Mac,
• a suitable USB-C to USB-C cable.

Apple states that around 32 GB of free storage is more than enough for the required files.

Apple Configurator is no longer strictly required

Older guides, including the previous version of this article, described restoration through Apple Configurator.

On current macOS versions, reviving or restoring can now be performed directly through the Finder on the host Mac.

Once the faulty Mac has been correctly placed in DFU mode, a corresponding DFU window appears in the Finder on the second Mac.

Use the right USB-C cable

This point is particularly important, because not every USB-C cable is suitable for a DFU restoration.

Apple requires a USB-C to USB-C cable that supports both data and charging on the second Mac.

An Apple USB-C charging cable that can also transfer data is suitable, for example.

The correct DFU port on the Mac

A common reason a Mac is not detected in DFU mode is using the wrong USB-C port.

On many Macs, not every USB-C or Thunderbolt port can be used for DFU mode. The affected Mac has a specific DFU port.

The port you must use depends on the particular Mac model.

Find the DFU port for your Mac model

Put a MacBook with an Apple chip into DFU mode

On a MacBook Air or MacBook Pro with an Apple chip, you need to use a specific keyboard shortcut.

Preparation

1. Connect both Macs to a power source.
2. Connect the USB-C cable to the correct DFU port on the affected MacBook.
3. Connect the other end to any USB-C port on the host Mac.
4. Where possible, remove all other USB devices from the affected Mac.
5. If the MacBook has MagSafe, you should use MagSafe for power.

Activate DFU mode

1. Hold down the power button or Touch ID button for up to 10 seconds until the MacBook turns off completely.
2. Briefly press and release the power button.
3. Immediately afterwards, hold down the following four keys at the same time:

On a MacBook with an Apple chip, hold all four keys down for approximately 10 seconds.

Then release Control, Option and Shift, but keep holding the power button.

Hold it for up to another 10 seconds until the DFU window appears in the Finder on the host Mac.

Put an Intel MacBook with a T2 chip into DFU mode

The keyboard shortcut is initially identical on an Intel MacBook with the T2 Security Chip:

• Left Control ⌃
• Left Option ⌥
• Right Shift ⇧
• Power button

The difference is the duration:

On a MacBook with a T2 chip, all four keys are held down together for approximately 3 seconds until the DFU window appears on the host Mac.

Put a Mac mini, Mac Studio, iMac or Mac Pro into DFU mode

The process is simpler on desktop Macs, but differs significantly from a MacBook.

Preparation

1. Connect the USB-C cable to the correct DFU port on the affected Mac.
2. Connect the other end to the host Mac.
3. Remove all other USB devices from the affected Mac.
4. Make sure the host Mac is turned on, connected to power and connected to the internet.

Start a desktop Mac in DFU

1. Disconnect the affected Mac completely from power.
2. Hold down the power button on the Mac.
3. While still holding the power button, reconnect the Mac to power.
4. Keep holding the power button.
5. Within approximately 10 seconds at the latest, the Mac should appear as a DFU device in the Finder on the host Mac.

Here too, the affected Mac's screen normally stays black.

Recognize DFU mode in the Finder

If everything worked, a new window appears in the Finder on the second Mac.

A device named Mac should appear in the sidebar. The main area indicates that this Mac is in DFU mode.

Two different options are now available:

• Revive Mac
• Restore Mac

Revive or restore a Mac: what is the difference?

Option 1: revive Mac firmware without erasing the Mac

This option should always be tried first.

Apple also calls this process Revive. It restores necessary firmware and Recovery components, among other things, without erasing the Mac's user data.

1. Select the Mac in the Finder's DFU window.
2. Click “Revive Mac” on the second Mac.
3. Confirm with “Continue” on the second Mac.
4. The host Mac downloads the required software from Apple.
5. Wait until the process is fully complete.

After a successful revive, the affected Mac normally restarts automatically.

On Macs with Apple chips, the startup options window may initially appear afterwards. In this case, select the normal startup volume, such as Macintosh HD.

Option 2: completely restore the Mac

If the firmware cannot be successfully revived, a complete restoration remains the option.

1. Select the DFU device in the Finder.
2. Click “Restore Mac” on the second Mac.
3. Confirm with “Restore & Update” on the second Mac.
4. The host Mac downloads the required firmware and system software from Apple.
5. Wait until the process is fully complete.

The affected Mac then normally restarts automatically.

What happens after restoration?

Mac with an Apple chip

On a Mac with an Apple chip, you may be asked to sign in with the Apple Account previously used with this Mac on the second Mac.

Setup Assistant then starts and the Mac can be set up again.

Intel Mac with a T2 Security Chip

A restored Intel Mac with a T2 chip may then initially start through macOS Internet Recovery.

After selecting the language, you may need to sign in with the previously used Apple Account. macOS can then be reinstalled.

The Mac does not appear in the Finder: what should you do?

If no DFU window appears, the cable, port or timing is usually the cause.

1. Check the Finder sidebar

Open:

Finder → Settings → Sidebar

Make sure “CDs, DVDs, and iOS Devices” is enabled.

2. Check the correct DFU port

The most common mistake is using the wrong USB-C port on the affected Mac.

Be sure to check which port on your Mac model is intended for DFU mode.

3. Use another USB-C cable

A USB-C cable may look correct but still only be suitable for charging.

Use a cable that is confirmed to support data transfer.

4. Remove other USB devices

Where possible, disconnect all unnecessary USB, Thunderbolt and other devices from the affected Mac.

5. Try the keyboard shortcut again

Especially on MacBooks, timing is crucial when activating DFU mode. If the device does not appear, turn it off completely again and repeat the keyboard shortcut.

A black screen does not automatically mean faulty firmware

A black screen can have many different causes. A DFU firmware revive should therefore not automatically be the first step for every black display.

Check beforehand, among other things:

• whether the Mac is actually turned on,
• whether an external display shows an image,
• whether power and the power adapter work,
• whether macOS Recovery can be started,
• whether the Mac appears in startup options,
• whether connected accessories prevent startup.

Firmware reviving becomes particularly interesting only when the usual measures do not help or the error occurred directly after an interrupted macOS installation.

Revive the firmware or reinstall macOS?

A normal macOS reinstallation and a firmware revive are two different procedures.

If macOS Recovery still works and only the operating system is damaged, a normal reinstallation of macOS is often sufficient.

Reinstall macOS: guide

If even the Recovery environment no longer starts correctly or the firmware is damaged, DFU mode may instead be required.

Alternative: create a bootable macOS USB drive

If the firmware works but you want to reinstall macOS or use a specific compatible macOS version, a bootable USB drive may be the better solution.

Create a bootable macOS USB drive

Frequently asked questions about Mac firmware restoration

Do I absolutely need a second Mac?

Yes. The DFU procedure described here requires a second working Mac as the host.

Does the second Mac also need an Apple chip?

No. The host Mac does not need the same chip as the faulty Mac. What matters is that the host Mac runs a sufficiently recent macOS version.

Does the second Mac need a T2 chip?

No. A T2 chip is not required on the second Mac even to revive a Mac with an Apple chip.

Do I need Apple Configurator?

Not strictly for Apple's current standard procedure. With current macOS, the Mac in DFU mode is displayed directly in the Finder and can be revived or restored there.

Does DFU mode erase my data?

DFU mode itself does not erase any data. “Revive Mac” is also intended to preserve data.

The “Restore Mac” option, however, erases the Mac completely.

Why does the screen stay black in DFU mode?

This is normal. While the affected Mac is in DFU mode, its display normally shows no image. The process is controlled through the second Mac.

Can I revive an M1, M2, M3 or M4 Mac this way?

Yes. The procedure is intended for Macs with Apple chips, so it also applies to the corresponding Mac generations with M1, M2, M3 and M4 as well as newer compatible Macs with Apple chips.

Restore Mac firmware: conclusion

A black screen or a Mac that no longer starts does not automatically mean a hardware fault. Especially after a failed or interrupted macOS installation, damaged firmware can be the cause.

Apple provides DFU mode for this on modern Macs. It requires the affected Mac, a second Mac with current macOS and a suitable USB-C data cable.

The most important rule:

If the damage is limited to firmware, this gives a good chance of making the Mac bootable again without having to erase its stored data.

Open Apple's official guide

Note: Reviving or restoring firmware should be performed carefully. A complete restoration erases all data on the Mac. If important data is not backed up and reviving without erasing does not succeed, consider professional help before taking further steps.